sampler samplerState;

float4 PShader(float2 texcoord : TEXCOORD0) : COLOR
{
	float4 color = tex2D(samplerState, texcoord);
	float4 gris = (0.3*color.r) + (0.55*color.g) + (0.15*color.b);
	color.r = gris;
	color.g = gris;
	color.b = gris;
	return color;
}

technique BlackWhite
{
	pass P0
	{
		PixelShader = compile ps_2_0 PShader();
	}
}